Control apparatus for washer-sterilizer

ABSTRACT

Disclosed is a washer-sterilizer apparatus having a water reservoir which supplies both the wash and rinse water and two pumps, one pump for pumping water from the reservoir for filling and rinsing and another for recirculating water in the washersterilizer during the wash cycle and draining. The reservoir is heated after filling to provide rinse water at a temperature higher than the wash water temperature. The apparatus controls are completely automatic and may be integrated with controls for loading and unloading devices to provide a completely automated system.

United States Patent Anderson et al.

[ CONTROL APPARATUS FOR WASHER- STERILIZER [72] Inventors: Edgar L.Anderson, Penfield; Michael L. Schneier, Pittsford, both of NY.

[73] Assignee: Sybron Corporation, Rochester,

[58] Field of Search ..l34/57 R, 57 D, 57 DL, 95, 134/99, 100,101,103,72, 68,131,134;

[151, 3,683,944 1451 Aug. 15,1972

2,197,382 Murphy ..134/95 x 2,621,666 12/1952 Hiort AfOrnas ..134/57 1)2,859,760 11/1958 Borell ..134/57 ox 3,221,754 12/1965 Robson et a1..l34/68 Primary Examiner-Walter A. Scheel Assistant Examiner-Philip R.Coe Attorney-Theodore B. Roessel 2 ABSTRACT Disclosed is awasher-sterilizer apparatus having a water reservoir which supplies boththe wash and rinse water and two pumps, one pump for pumping water fromthe reservoir for filling and rinsing and another a for recirculatingwater in the washer-sterilizer during the wash cycle and draining. Thereservoir is heated after filling to provide rinse water at atemperature 68/ 12 R higher than the wash water temperature. Theapparatus controls are completely automatic and may be [56] Reierencescued integrated with controls for loading and unloading UNI STATESPATENTS devices to provide a completely automated system.

3,049,133 8/1962 Jacobs ..l34/57 D 10 Claims,'2 Drawing Figures STEAMPatented Aug. 15, 1972 N B m mm m R w w v m m L Du A G D m E mm 1 9 i Qt mm a l e h 4 m 8 av M ON 5 2 Nbj a %x E I $2; W J N- um ow( A m- N- w2E5 mm F mm lwwl -65:

BY MICHAEL LSCHNEIER H OI ATTORNEY CONTROL APPARATUS FOR WASHER-STERILIZER BACKGROUND OF THE INVENTION The present invention relates toa washer-sterilizer apparatus particularly for use by pharmaceuticalmanufacturers, hospitals, laboratories and the like. Specifically, theinvention relates to a washer-sterilizer having a water reservoir fromwhich is drawn the wash and rinse water. The water in the reservoir istemperature controlled to provide optimum washing and rinsingtemperatures. The controls for regulating the temperature of the waterin the reservoir are integrated with both the controls for operating thewasher-sterilizer, and the loader and unloader controls therebyproviding a fully automated system.

Prior art washer-sterilizer units which drew wash and rinse waterdirectly from the buildings water supply had several drawbacks includinga long fill cycle in areas of low water pressure. Since the fill cycledepended upon the water pressure in the building, the length of the tillcycle might vary as the water pressure varied. This required anadditional control function to compensate for this varying fill time.Further, since the unit was connected to the water supply of thebuilding, the temperature of the wash and rinse cycles were dependentupon the temperature of this water supply.

The present invention provides a separate reservoir tank associated withthe washer-sterilizer including a pump for drawing water from thereservoir and a water reservoir temperature control. With thisarrangement, the till time and water temperature are not sensitive tothe pressure and temperature of thebuilding water supply. For example,the fill cycle does not depend upon line pressure in the building butfilling to a desired level may be accomplished quickly and accurately bypumping water from the reservoir into the washing apparatus. Thetemperature of water in the reservoir can be varied between the wash andrinse cycles to provide gradually increasing temperatures during thewash cycle and a high temperature rinse cycle. This gradual temperatureincrease to the eventual hot water rinse is particularly useful toprevent protein material from cooking-on the articles being washed. Whensteam is used during the sterilizing cycle, controls are provided forutilizing the steam to control the water temperature during the wash andrinse portion of the operating cycle.

SUMMARY OF THE PRESENT INVENTION The present invention may becharacterized in one aspect thereof by the provision of a waterreservoir associated with the washer-sterilizer apparatus; a first pumpfor pumping water from the reservoir into the washer sterilizer forfilling and rinsing; a second pump for recirculating the water duringwashing and for draining; and control means including a watertemperature controller, said control means being integrated with controlfor the washer-sterilizer loading and unloading apparatus to provide afully automated system.

OBJECTS OF THE INVENTION An object of the present invention is toprovide a washer-sterilizer having a ready supply of both wash and rinsewater at a controlled temperature wherein operation of the apparatus isnot sensitive to the normal building water supply as to temperature,pressure or rate of flow.

A further object of the present invention is to provide awasher-sterilizer having means for filling the washing chamber with washwater quickly and accurately independent of the line pressure.

Yet another object of the present invention is to provide a washersterilizer and an associated water reservoir having integrated controlsfor operating the washer sterilizer and controlling the temperature ofthe water in the reservoir.

Still another object of the present invention is to pro: vide awasher-sterilizer having controls which may be integrated with thecontrols of an automatic loader-underloader provide a fully automatedsystem.

Yet another object of the present invention is to provide awasher-sterilizer apparatus which has an optimum size pump for fillingand rinsing and a second, larger, pump for recirculating the waterduring washing and then draining.

These and other objects, advantages and characterizing features of thepresent invention will become more apparent upon consideration of thefollowing detailed description thereof when taken in connection with theaccompanying drawings depicting the same.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of the washersterilizer apparatus of the present invention; and

FIG. 2 is a block diagram of the control circuit of the washersterilizer of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawing, FIG.1 shows the washersterilizing vessel generally indicated at 10. Thevessel is preferably of the type which allows pass-through operation,that is, it has a loading door 12 at one end of a vessel chamber 8 andan unloading door 14 at another end of the vessel chamber. These doorsmay be operated by means (not shown) to slide the doors over the loadand unload openings of chamber 8. Appropriate limit switches as shown inthe schematic of FIG. 2 are provided at both the load and unload doorsto indicate when the doors are fully open or closed. Suitable load andunload mechanism represented schematically by conveyors 16 and 18respectively are provided for passing the articles to be washed andsterilized into and out of the vessel.- It should be understood thatconveyors 16 and 18 only schematically represent the mechanisms forpassing the articles to be washed and sterilized into and through vessel10. These articles, in the case of hospital operation, may be suchthings as operating room instruments and apparatus, patient roomequipment, bed pans trays, dishes or the like. Such items usually arecontaminated with some sort of protein material which must be kept fromcookingon during the washing and sterilizing cycles. Accordingly, such.articles are usually washed with water at one temperature to preventcoagulation of protein and then rinsed with water at a highertemperature before sterilizing.

In order to provide accurate controlof the wash and rinse watertemperatures, a reservoir tank 20 is provided for storing the water usedduring the wash and rinse cycles. This reservoir is connected to andfilled from the normal water supply of the building by main line 22 andpipe 24. A solenoid valve SV-4 controls flow through pipe 24. Thereservoir is also provided with two temperature sensors and a liquidlevel controller TS-2, TS-3, and LLC-2 respectively which operate in themanner described hereinbelow.

Water is pumped from reservoir 20 through a pipe 26 by a fill pump 28which has its outlet side connected by means of pipes 30 and 32 tovarious spray headers 34 located with chamber 8. A level controllerLLC-l determines the amount of wash water pumped into the chamber. Theoutlet of pump 28 is also connected to an aspirator 36 for introducingdetergent from a detergent tank 38 into line 30. Flow of the detergentis turned on and off by the operation of a solenoid valve SV- which liesin line 40 connecting the outlet of the pump to the aspirator and line30.

Vessel has a sump portion 42 which is connected by a pipe 44 to theinlet of a recirculating pump 46. The outlet of recirculating pump 46 isconnected to a Y- strainer 48. Y-strainer 48 has one branch 48 (a)connected to pipe 50 which in turn is connected to lines 32 forpurposes. of recirculating the wash water within chamber 8 during thewash cycle. Pipe 50 is provided with a temperature sensor TS-l whichmonitors the temperature of the recirculating water for purposes set outhereinbelow. The other branch 48(1)) of the Y- strainer is connected bya drain pipe 52 to a waste drain 54. Drain pipe 52 is opened and closedby a solenoid valve SV-l.

The sterilizing cycle of operation is accomplished with steam whereinthe steam is not only used for sterilizing but also for heating thewater in reservoir tank and for sealing the load and unload doors 12 and14 of the washer-sterilizer vessel. To accomplish this, a main steamsupply line 56 which is connected to a steam source (not shown) has onebranch line 58 connected to water reservoir 20. A solenoid valve SV-3 inbranch 58 controls the flow of steam to the reservoir. A second branchline 60 is connected to the washer sterilizer vessel 10 and opens intochamber 8. A solenoid valve SV-2 in branch line 60 and operated by atemperature sensor TS-4 controls the flow of steam to the chamber of thewasher-sterilizer. A third branch line 62 is connected by means of pipes62(a) and (b) to' the load and unload door seals 64 and 66 respectively.The particular operation of these seals will not be described in detailhere as they are more particularly described in a co-pendingapplication, Ser. No. 32,284. It is sufficient for purposes of thepresent invention merely to say that when steam issupplied to the seals,gaskets are moved into position to seal the doors against the chamberopenings. A cam operated valve V-l opens and closes branch line 62wherein this cam valve is operated by a drive motor 68.

A steam exhaust line 72 "which is connected to branch line 62 is openedand closed by a cam valve V-3 also operated by drive motor 68 to ventsteam from seals 64 and 66 so that the load and unload doors can beopened. Steam exhaust line 72 is connected to a water ejector 74, thewater ejector in turn being connected by pipe 76 to the main watersupply line 22. A cam valve V-2 also operated by drive motor 68 opensand closes this water line to the ejector.

Completing the connections to the washer-sterilizer is a chamber ventpipe 70 and a branch water line 78. Chamber vent pipe 70 whichcommunicates with chamber 8 through line 60 is opened and closed by acam valve V-S. Water branch line 78 is connected to a coil 80 located insump 42 for purposes of circulating water through the sump to cool andcollapse the steam within chamber 8 at the end of the sterilizing cycle.A

vacuum switch VS-l provided for purposes set out hereinbelow indicateswhen a predetermined vacuum is drawn in chamber 8 by the collapsingsteam.

Line 78 is opened and closed by a cam valve V-4 operated by drive motor68 with water from the coil being discharged through line 82 to drain54. Two additional drail lines 84 and 86 extend from sump 42 to drain.These drain lines 84 and 86 are opened and closed by solenoid valvesSV-9 and SV-6 respectively. One of the drain lines, 84, is connected toejector 74.

FIG. 2 shows in block diagram form the various circuits for controllingthe operation of the washer-sterilizer. These circuits are opened orclosed by various cam switches (CS) operated by drive motor 68 asdescribed hereinbelow. While not shown, it should be understood thateach cam switch has an open and a closed contact so' that certain of theswitches may actuate one circuit when open and another when closed.

The main power on-off switch has not been shown for purposes ofsimplifying the description of the operation and it is understood thatpower must be on in order to energize the controls shown in FIG. 2.Various safety devices which can shut down operation at any point in thecycle have also, been not shown, in order to simplify the description.

Referring to FIGS. 1 and 2, the operation will be described as beginningwith the unload 14 door closed and load door 12 open; indexing motor 68in the off position; and the articles to be washed and sterilized readyfor loading into vessel 10 by load conveyor 16. In this position,limitswitches on the load door, which are in a condition indicating that loaddoor 12 is fully open, delivers power to the loader circuit which inturn operates the loading mechanism represented by conveyor l6.

While the vessel is being loaded, the level and temperature of the wateris reservoir 20 is adjusted by power through CS-S (NC). In this respect,water level sensor LLC-2 may close a circuit to open solenoid SV- 4 toadmit water to the reservoir while a circuit through cam switches CS5and CS-7 acting through temperature sensor TS-2 operates solenoid SV-3to admit steam into the reservoir as necessary to bring the water towash temperature.

When loading is complete, a feed back from the load conveyor drivethrough the loader circuit (FIG. 2) activates the load door motor toclose load door 12. When the load door is closed, power is delivered bythe limit switches (now indicating that the load door is closed) to thedrive circuit of motor 68 to index the drive motor to the second or washposition. At this wash position, cam switch CS-l is actuated, cam switchCS-7 is deactuated and connected to temperature sensor TS-3 and camvalve V-l is opened.

Connecting CS-8 to temperature sensor TS-3 causes solenoid SV-3 to opento introduce steam into reservoir 20 for bringing the reservoir water upto rinse temperature.

Opening V-l admits steam to he gaskets of seals 64 and 66 (FIG. 1) toseal the load and unload doors against the vessel.

Actuating cam switch CS-l completes a circuit through the liquid levelcontroller LLC-1 to start fill pump 28 and open solenoid SV-S. SolenoidSV-S is opened to permit a portion of the water from the pump outlet toflow through line 40 and aspirator 36. This draws liquid detergent fromliquid detergent container 38 and mixes detergent with the fill waterflowing into the vessel through line 30 and 32. Pump 28 continues tooperate until LLC-1 is satisfiedie. the water in vessel chamber 8reaches the desired level. When this occurs, the circuit through LLC-lto fill pump 28 and'SV- 5 is opened to stop the fill motor and close thedetergent solenoid SV-S. When LLC-l is satisfied, another circuit isclosed through LLC-l to start recirculating pump 46. The recirculatingpump pumps the water-de tergent mixture from sump 42 through line 44, Y-strainer branch 48(a), lines 50 and 32 into the vessel through sprayheaders 34. The recirculating pump has a higher power rating thanfilling pump 28 so that the water detergent mixture is sprayed withconsiderable force through spray headers 34 to wash the articles withinthe vessel.

The temperature of the recirculating water detergent mixture ismonitored by temperature sensor TS-l in line 50. This temperature sensoris connected to solenoid valve SV-2 and operates to open or close SV-2to introduce steam into the vessel as necessary to maintain the properwashing temperature. While the articles are being washed, LLC-2 opensSV-4 so that reservoir tank 20 is refilled.

When recirculating pump 46 is started, a wash timer TR-l is alsostarted. At the end of the timed wash period, the timing out of timerTR-l overrides TS-l and deenergizes SV-2. Also, when TR-l times out, acircuit is made through a drain time delay relay TDR-l to drain solenoidvalves SV-l and SV-6 to open the drain lines 52 and 86. With drainsolenoid SV-l opened, continued operation of recirculating pump 46 willnow direct the water detergent mixture through arm 48(b) of theY-strainer and line 52 to waste drain 54. This also cleans the drainscreen 48(c). Screen 48(c) which lies across arm 48(a) prevents thecirculation of solid material washed from the articles in chamber 8 backto the chamber. However, the screen is arranged so that as water isflowing to drain, the screen is cleaned and the solid material collectedon the screen also flushed to the drain. Solenoid valve SV-6 is alsoopened to assist in the draining of the water detergent mixture fromsump 42 through line 86.

When time delay relay TDR-l times out, the motor drive circuit isactuated to index the motor to the third or rinse positionfTWhen themotor is indexed to the rinse position, cam switches CS-2 and CS-4 areactuated. Actuating cam switch CS-2 opens solenoid SV-2; starts a rinsetime delay relay TDR-Z to time the rinse cycle; and arms a circuit whichis capable of delivering power to fill pump 28. Actuating CS-4 completesa circuit to a pulse timer circuit which delivers power to a pulsemotor. Operation of the pulse motor opens and closes a switch in thearmed" fill pump circuit to start fill pump 28. In this manner, fillpump 28 is operated intermittently to spray water through headers 34 inpulses which increases the effectiveness of the rinsing operation.During this rinse period, solenoid valves SV- 1 and SV-6 are held openby a circuit through CS-4 so that the rinse water is flushed to thewaste drain.

With solenoid SV-2 open steam is introduced into chamber 8 through line60 which helps to push the rinse water out through the open. drains 52and 86. At the end of the rinse period, TDR-2 times out causing motor 68to index to the fourth or sterilizing position. As the motor is indexedto the sterilizing position, CS-2 and CS4 are deactuated to open thecircuit to fill pump 28, the pulse timer and solenoid valves SV-l and SAt the sterilizing position, motor 68 operates to open cam valve V-2 andcam switch CS-S and close cam switches CS-9. With valve V-2 opened,water flows through lines 22 and 76 through ejector 74. Power throughCS-10 (N.C.) opens solenoid valve SV-9 so that the water flowing throughejector 74 can pull any condensate and air from vessel 10 and dischargeit to the waste drain 54. A trap 87 in line 84 prevents the escape ofsteam but allows the passage of condensate to the waste drain. In thismanner, condensed steam is continuously removed from the vesselthroughout the sterilizing cycle. Closing cam switch CS-9 completes acircuit through contact (a) of a dual contact tempera ture sensor TS-4to steam solenoid valve SV-2 and opening CS-S breaks the circuit to SV-3so that all available steam is directed into vessel 10. When thesterilizing temperature is reached, contact (12) of temperature switchT84 is closed to start a sterilize time delay relay TDR-3 which timesthe sterilizing cycle. Temperature switch TS-4 continues to operatethrough contact (a) to open or close SV-2 for adding steam as necessaryto maintain the sterilizing temperature.

At theend of timed sterilizing cycle, TDR-3 closes the motor drivecircuit to index motor 68 to the fifth or evacuate position. As motor 68indexes to the evacuate position, cam switches CS6 and CS-9 aredeactuated, CS-10 actuated and cam valve V4 is opened. Deactuating CS-9causes steam solenoid SV-Z to close while opening valve V-4 allows waterto circulate through coil 80 to collapse the steam in the vessel chamber8. Actuating cam switch CS-l0 holds solenoid SV 9 open through theevacuate cycle. When a predetermined vacuum is drawn in the vesselchamber 8 by collapsing the steam, a vacuum switch VS-l closes to startmotor 68 indexing through the sixth or vent position to the seventh orcycle complete" position.

In the vent position, cam valve V-2 remains open to continue flow ofwater to the ejector. Also, in the vent position, cam valve V4 isclosed; cam valve V-3 is opened to vent steam from gaskets 64 and 66 andunseal the load and unload doors; and cam valve V-5 is opened to ventchamber 8 to bring the chamber back to atmospheric pressure.

As motor 68 indexes to the cycle complete" position, cam switch CS-ll isactuated to energize the un loader circuit. The unloader circuit firststarts the unload door motor to open the unload door 14. When the unloaddoor is full open, the unloader circuit causes the motor drive circuitto close to begin indexing motor 68 to the off position. In moving tothe off position, CS- 1 1 is deactuated, however, the unloader circuitremains powered by a circuit through limit switches at the unload doorwhich indicate that the unload door is full open. Thus, the unloadercircuit continues to function to power the unload mechanism representedby unload conveyor 18 to unload the washed and sterilized aiticles. Whenthe unload cycle is complete, a feedback from the unload conveyor drivethrough the unloader circuit activates the door closing mechanism. Whenthe unload door is closed, the limit switch associated with the unloaddoor delivers power through the load door limit switches and loadcircuit to open the load door to begin the loading cycle.

Accordingly, it should by appreciated that the present inventionaccomplishes its intended objects in providing a washer-sterilizerhaving a ready supply of bath wash and rinse water at the propertemperature. The use of two separate pumps, one for filling and rinsing,and another, larger pump for washing provides an efficient means ofperforming these functions. Further efficiency is gained by employingthe sterilizing medium, steam, to perform other functions such asheating the reservoir water, maintaining the proper wash temperature andassisting in the removal of water from the vessel and by integrating thewasher-sterilizer controls with the loader and unloader controls toprovide a fully automated system.

While a preferred embodiment of the present invention has beendescribed, it should be appreciated that various modifications arewithin the skill of the art. For example, another reservoir, reservoirwater controls, a second fill pump and appropriate controls may be incorporated into the present design to provide a distill water or otherspecial rinse which would be employed after the normal rinse occurringat the third position.

Having thus described the invention, what is claimed as new is:

l. Washer apparatus comprising in combination:

a. a closed vessel having an opening therein for receiving the articlesto be washed including means for closing and sealing said opening;

b. a water reservoir tank having a water level and temperature controlmeans;

cfa conduit connecting said water reservoir tank to said vessel andterminating in a plurality of spray nozzles within said vessel;

. a first fill pump for pumping water from said water reservoir tankthrough said conduit and into said vessel;

e. a second recirculating pump having its inlet and outlet communicatingwith said vessel for recirculating the water in said vessel to wash thearticles therein;

f. an electric circuit having a first portion operatively connected tosaid fill pump and a second portion operatively connected to saidrecirculating pump;

. a water fill control means in said vessel for opening said firstcircuit portion and closing said second circuit portion when the waterin said vessel reaches a predetermined level; and means in said electriccircuit for disabling said fill control means when said circuit to saidrecirculating pump is closed.

2. Apparatus as set forth in claim 1 including rinse control means forrinsing said articles after a predeter- -mined timed wash interval, saidrinse control means comprising: i

a. a first electric including said fill pump;

b. a second electric circuit including a pulse timer for opening andclosing said first circuit including a pulse timer for opening andclosing said first circuit to cycle said fill pump on and off forpredetermined timed intervals; and

c. a timer for deenergizing said first and second circuit after apredetemlined timed rinse interval.

3. Apparatus as set forth in claim 2 comprising means for heating thewater in said reservoir prior to operation of said rinse control meanswhereby water from said reservoir used during rinsing is at a highertemperature than water from said reservoir used during washing.

4. Washer-sterilizer apparatus and controls therefore comprising:

a. a closed vessel having an opening therein for receiving the articlesto be washed and sterilized including means for closing and sealing saidopenmg;

b. a water reservoir tank exterior of said vessel having a reservoirwater level and temperature control means, said reservoir supplyingwater to said vessel for washing and rinsing said articles;

c. a conduit connecting said reservoir and said vessel;

d. a first, fill pump for pumping water from said reservoir through saidconduit and into said vessel;

e. a second, recirculating pump for recirculating water in said vesselto wash said articles;

f. a first electric circuit including water level control means forstopping said fill pump and starting said recirculating pump when thewater level in said vessel has reached a predetermined level and a timerfor opening said electric circuit after said recirculating pump hasoperated for a timed wash period; and

. a second electric circuit including means for introducing asterilizing medium into said vessel and a timer for opening said secondcircuit after a predetermined timed sterilizing interval, said secondelectrical circuit being initially closed after said first circuit isopened.

5. Apparatus as set forth in claim 4 comprising:

a. a third electric circuit including said fill pump;

b. a fourth electric circuit including a pulse timer for opening andclosing said third circuit to cycle said fill pump on and off to rinsesaid articles;

c. means activating said third and fourth circuits after said firstcircuit is opened; and

d. a rinse timer in said third circuit adapted to open said third andfourth circuits after a predetermined timed rinse period.

6. Apparatus as set forth in claim 4 wherein said sterilizing medium issteam, said apparatus further comprising:

a. a valved steam conduit connecting said vessel to a source of steam;

b. a valved branch line extending from said steam conduit into saidreservoir tank; and

c. said reservoir water level and temperature control means beingoperatively connected to said branch line valve to open and close thesame responsive to the temperature of water in said reservoir.

7. Apparatus as set forth in claim 6 wherein said means for closing andsealing said vessel opening comprises:

a. a steam operated seal;

b. a second valved branch line connecting said steam conduit to saidsteam operated seal; and

c. means for opening said second branch line to effect said seal.

8. Apparatus as set forth in claim 4 comprising: I

a. said vessel having said load opening at one end thereof and an unloadopening at an opposite end;

b. limit switches associated with said load and unload openings forindicating when said openings are full open and full closed; I

c. loader means adjacent said load opening and unloader means adjacentsaid unload opening for moving said articles into and out of saidvessel; and

d. a third electric circuit including said limit switches and loader andunloader means, said electric cir cuit having a first portion activatingsaid loader means when said load opening is full open and a secondportion activating said unloader means when said unload opening is fullopen.

9. Apparatus as set forth in claim 8, wherein said 10. A washing andsterilizing apparatus having a wash cycle, a rinse cycle and asterilizing cycle, comprising in combination:

a. a vessel having a load opening at one end thereof and an unloadopening at an opposite end to persaid wash cycle and thereafter for saidrinse cycle and said second pump for recirculating water in said vesselduring said wash cycle;

f. means for controlling the operation of said pumps during said washand rinse cycles;

g. means for introducing steam into said vessel during said sterilizingcycle;

h. loader means adjacent said loadopening and unloader means adjacentsaid unload opening for moving articles into and out of said vessel; and

i. an electric circuit including said limit switches, loader means andunloader means, said circuit having a first portion activating saidloader means when said load opening is full open and the second portionactivating said unloader means when said unload opening is full open.

@ 3 3 UNITED STATES PATENT ormcE CE'NFKCATE OF C ECTION Patent No. 3,3,9 Dated August 15, 1972 Inventor-( Edgar L. Anderson and Michael L.Schneier It is certified that error appears in the above-identifiedpatent and that said Letters Patent are hereby corrected as shown below:

Column 2, line 16 after "deloader" insert --to-. Column line 45 "is"first instance should read -to--. Column 5, line 1 "he" should read-the-. Column 7, line 66 after "electric" insert --circuit,.

Column 8, line 2- cancel "including a pulse timer for opening andclosing said first circuit".

Signed and sealed this 20th day of March 1973.

(SEAL) Attest:

V EDWARD M@FLETCHER,JR., Y ROBERT GOTTSCHALK Attesting OfficerCommissioner of Patents

1. Washer apparatus comprising in combination: a. a closed vessel havingan opening therein for receiving the articles to be washed includingmeans for closing and sealing said opening; b. a water reservoir tankhaving a water level and temperature control means; c. a conduitconnecting said water reservoir tank to said vessel and terminating in aplurality of spray nozzles within said vessel; d. a first fill pump forpumping water from said water reservoir tank through said conduit andinto said vessel; e. a second recirculating pump having its inlet andoutlet communicating with said vessel for recirculating the water insaid vessel to wash the articles therein; f. an electric circuit havinga first portion operatively connected to said fill pump and a secondportion operatively connected to said recirculating pump; g. a waterfill control means in said vessel for opening said first circuit portionand closing said second circuit portion when the water in said vesselreaches a predetermined level; and h. means in said electric circuit fordisabling said fill control means when said circuit to saidrecirculating pump is closed.
 2. Apparatus as set forth in claim 1including rinse control means for rinsing said articles after apredetermined timed wash interval, said rinse control means comprising:a. a first electric including said fill pump; b. a second electriccircuit including a pulse timer for opening and closing said firstcircuit including a pulse timer for opening and closing said firstcircuit to cycle said fill pump on and off for predetermined timedintervals; and c. a timer for deenergizing said first and second circuitafter a predetermined timed rinse interval.
 3. Apparatus as set forth inclaim 2 comprising means for heating the water in said reservoir priorto operation of said rinse control means whereby water from saidreservoir used during rinsing is at a higher temperature than water fromsaid reservoir used during washing.
 4. Washer-sterilizer apparatus andcontrols therefore comprising: a. a closed vessel having an openingtherein for receiving the articles to be washed and sterilized includingmeans for closing and sealing said opening; b. a water reservoir tankexterior of said vessel having a reservoir water level and temperaturecontrol means, said reservoir supplying water to said vessel for washingand rinsing said articles; c. a conduit connecting said reservoir andsaid vessel; d. a first, fill pump for pumping water from said reservoirthrough said conduit and into said vessel; e. a second, recirculatingpump for recirculating water in said vessel to wash said articles; f. afirst electric circuit including water level control means for stoppingsaid fill pump and starting said recirculating pump when the water levelin said vessel has reached a predetermined level and a timer for openingsaid electric circuit after said recirculating pump has operated for atimed wash period; and g. a second electric circuit including means forintroducing a sterilizing medium into said vessel and a timer foropening said second circuit after a predetermined timed sterilizinginterval, said second electrical circuit being initially closed aftersaid first circuit is opened.
 5. Apparatus as set forth in claim 4comprising: a. a third electric circuit including said fill pump; b. afourth electric circuit including a pulse timer for opening and closingsaid third circuit to cycle said fill pump on and off to rinse saidarticles; c. means activating said third and fourth circuits after saidfirst circuit is opened; and d. a rinse timer in said third circuitadapted to open said third and fourth circuits after a predeterminedtimed rinse period.
 6. Apparatus as set forth in claim 4 wherein saidsterilizing medium is steam, said apparatus further comprising: a. avalved steam conduit connecting said vessel to a source of steam; b. avalved branch line extending from said steam conduit into said reservoirtank; and c. said reservoir water level and temperature control meansbeing operatively connected to said branch line valve to open and closethe same responsive to the temperature of water in said reservoir. 7.Apparatus as set forth in claim 6 wherein said means for closing andsealing said vessel opening comprises: a. a steam operated seal; b. asecond valved branch line connecting said steam conduit to said steamoperated seal; and c. means for opening said second branch line toeffect said seal.
 8. Apparatus as set forth in claim 4 comprising: a.said vessel having said load opening at one end thereof and an unloadopening at an opposite end; b. Limit switches associated with said loadand unload openings for indicating when said openings are full open andfull closed; c. loader means adjacent said load opening and unloadermeans adjacent said unload opening for moving said articles into and outof said vessel; and d. a third electric circuit including said limitswitches and loader and unloader means, said electric circuit having afirst portion activating said loader means when said load opening isfull open and a second portion activating said unloader means when saidunload opening is full open.
 9. Apparatus as set forth in claim 8,wherein said third circuit operates to close said first circuit aftersaid limit switches indicate that said load and unload openings areclosed, said third circuit in turn being operated to open said unloadopening after said second circuit is opened.
 10. A washing andsterilizing apparatus having a wash cycle, a rinse cycle and asterilizing cycle, comprising in combination: a. a vessel having a loadopening at one end thereof and an unload opening at an opposite end topermit movement of articles into, through and out of said vessel; b.means for closing and sealing said openings; c. limit switchesassociated with said load and unload openings for indicating when saidopenings are fully open and fully closed; d. a reservoir tank forsupplying wash and rinse water to said vessel, said tank including meansfor controlling the level and temperature of the water therein; e. firstand second pumps, said first pump for pumping water from said reservoirinto said vessel for said wash cycle and thereafter for said rinse cycleand said second pump for recirculating water in said vessel during saidwash cycle; f. means for controlling the operation of said pumps duringsaid wash and rinse cycles; g. means for introducing steam into saidvessel during said sterilizing cycle; h. loader means adjacent said loadopening and unloader means adjacent said unload opening for movingarticles into and out of said vessel; and i. an electric circuitincluding said limit switches, loader means and unloader means, saidcircuit having a first portion activating said loader means when saidload opening is full open and the second portion activating saidunloader means when said unload opening is full open.